1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2007-2017 Nicira, Inc. 4 */ 5 6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 8 #include <linux/skbuff.h> 9 #include <linux/in.h> 10 #include <linux/ip.h> 11 #include <linux/openvswitch.h> 12 #include <linux/netfilter_ipv6.h> 13 #include <linux/sctp.h> 14 #include <linux/tcp.h> 15 #include <linux/udp.h> 16 #include <linux/in6.h> 17 #include <linux/if_arp.h> 18 #include <linux/if_vlan.h> 19 20 #include <net/dst.h> 21 #include <net/ip.h> 22 #include <net/ipv6.h> 23 #include <net/ip6_fib.h> 24 #include <net/checksum.h> 25 #include <net/dsfield.h> 26 #include <net/mpls.h> 27 #include <net/sctp/checksum.h> 28 29 #include "datapath.h" 30 #include "flow.h" 31 #include "conntrack.h" 32 #include "vport.h" 33 #include "flow_netlink.h" 34 35 struct deferred_action { 36 struct sk_buff *skb; 37 const struct nlattr *actions; 38 int actions_len; 39 40 /* Store pkt_key clone when creating deferred action. */ 41 struct sw_flow_key pkt_key; 42 }; 43 44 #define MAX_L2_LEN (VLAN_ETH_HLEN + 3 * MPLS_HLEN) 45 struct ovs_frag_data { 46 unsigned long dst; 47 struct vport *vport; 48 struct ovs_skb_cb cb; 49 __be16 inner_protocol; 50 u16 network_offset; /* valid only for MPLS */ 51 u16 vlan_tci; 52 __be16 vlan_proto; 53 unsigned int l2_len; 54 u8 mac_proto; 55 u8 l2_data[MAX_L2_LEN]; 56 }; 57 58 static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage); 59 60 #define DEFERRED_ACTION_FIFO_SIZE 10 61 #define OVS_RECURSION_LIMIT 5 62 #define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2) 63 struct action_fifo { 64 int head; 65 int tail; 66 /* Deferred action fifo queue storage. */ 67 struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE]; 68 }; 69 70 struct action_flow_keys { 71 struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD]; 72 }; 73 74 static struct action_fifo __percpu *action_fifos; 75 static struct action_flow_keys __percpu *flow_keys; 76 static DEFINE_PER_CPU(int, exec_actions_level); 77 78 /* Make a clone of the 'key', using the pre-allocated percpu 'flow_keys' 79 * space. Return NULL if out of key spaces. 80 */ 81 static struct sw_flow_key *clone_key(const struct sw_flow_key *key_) 82 { 83 struct action_flow_keys *keys = this_cpu_ptr(flow_keys); 84 int level = this_cpu_read(exec_actions_level); 85 struct sw_flow_key *key = NULL; 86 87 if (level <= OVS_DEFERRED_ACTION_THRESHOLD) { 88 key = &keys->key[level - 1]; 89 *key = *key_; 90 } 91 92 return key; 93 } 94 95 static void action_fifo_init(struct action_fifo *fifo) 96 { 97 fifo->head = 0; 98 fifo->tail = 0; 99 } 100 101 static bool action_fifo_is_empty(const struct action_fifo *fifo) 102 { 103 return (fifo->head == fifo->tail); 104 } 105 106 static struct deferred_action *action_fifo_get(struct action_fifo *fifo) 107 { 108 if (action_fifo_is_empty(fifo)) 109 return NULL; 110 111 return &fifo->fifo[fifo->tail++]; 112 } 113 114 static struct deferred_action *action_fifo_put(struct action_fifo *fifo) 115 { 116 if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1) 117 return NULL; 118 119 return &fifo->fifo[fifo->head++]; 120 } 121 122 /* Return true if fifo is not full */ 123 static struct deferred_action *add_deferred_actions(struct sk_buff *skb, 124 const struct sw_flow_key *key, 125 const struct nlattr *actions, 126 const int actions_len) 127 { 128 struct action_fifo *fifo; 129 struct deferred_action *da; 130 131 fifo = this_cpu_ptr(action_fifos); 132 da = action_fifo_put(fifo); 133 if (da) { 134 da->skb = skb; 135 da->actions = actions; 136 da->actions_len = actions_len; 137 da->pkt_key = *key; 138 } 139 140 return da; 141 } 142 143 static void invalidate_flow_key(struct sw_flow_key *key) 144 { 145 key->mac_proto |= SW_FLOW_KEY_INVALID; 146 } 147 148 static bool is_flow_key_valid(const struct sw_flow_key *key) 149 { 150 return !(key->mac_proto & SW_FLOW_KEY_INVALID); 151 } 152 153 static int clone_execute(struct datapath *dp, struct sk_buff *skb, 154 struct sw_flow_key *key, 155 u32 recirc_id, 156 const struct nlattr *actions, int len, 157 bool last, bool clone_flow_key); 158 159 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, 160 struct sw_flow_key *key, 161 const struct nlattr *attr, int len); 162 163 static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key, 164 __be32 mpls_lse, __be16 mpls_ethertype, __u16 mac_len) 165 { 166 int err; 167 168 err = skb_mpls_push(skb, mpls_lse, mpls_ethertype, mac_len, !!mac_len); 169 if (err) 170 return err; 171 172 if (!mac_len) 173 key->mac_proto = MAC_PROTO_NONE; 174 175 invalidate_flow_key(key); 176 return 0; 177 } 178 179 static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key, 180 const __be16 ethertype) 181 { 182 int err; 183 184 err = skb_mpls_pop(skb, ethertype, skb->mac_len, 185 ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET); 186 if (err) 187 return err; 188 189 if (ethertype == htons(ETH_P_TEB)) 190 key->mac_proto = MAC_PROTO_ETHERNET; 191 192 invalidate_flow_key(key); 193 return 0; 194 } 195 196 static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key, 197 const __be32 *mpls_lse, const __be32 *mask) 198 { 199 struct mpls_shim_hdr *stack; 200 __be32 lse; 201 int err; 202 203 stack = mpls_hdr(skb); 204 lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask); 205 err = skb_mpls_update_lse(skb, lse); 206 if (err) 207 return err; 208 209 flow_key->mpls.lse[0] = lse; 210 return 0; 211 } 212 213 static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key) 214 { 215 int err; 216 217 err = skb_vlan_pop(skb); 218 if (skb_vlan_tag_present(skb)) { 219 invalidate_flow_key(key); 220 } else { 221 key->eth.vlan.tci = 0; 222 key->eth.vlan.tpid = 0; 223 } 224 return err; 225 } 226 227 static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key, 228 const struct ovs_action_push_vlan *vlan) 229 { 230 if (skb_vlan_tag_present(skb)) { 231 invalidate_flow_key(key); 232 } else { 233 key->eth.vlan.tci = vlan->vlan_tci; 234 key->eth.vlan.tpid = vlan->vlan_tpid; 235 } 236 return skb_vlan_push(skb, vlan->vlan_tpid, 237 ntohs(vlan->vlan_tci) & ~VLAN_CFI_MASK); 238 } 239 240 /* 'src' is already properly masked. */ 241 static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_) 242 { 243 u16 *dst = (u16 *)dst_; 244 const u16 *src = (const u16 *)src_; 245 const u16 *mask = (const u16 *)mask_; 246 247 OVS_SET_MASKED(dst[0], src[0], mask[0]); 248 OVS_SET_MASKED(dst[1], src[1], mask[1]); 249 OVS_SET_MASKED(dst[2], src[2], mask[2]); 250 } 251 252 static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key, 253 const struct ovs_key_ethernet *key, 254 const struct ovs_key_ethernet *mask) 255 { 256 int err; 257 258 err = skb_ensure_writable(skb, ETH_HLEN); 259 if (unlikely(err)) 260 return err; 261 262 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 263 264 ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src, 265 mask->eth_src); 266 ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst, 267 mask->eth_dst); 268 269 skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 270 271 ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source); 272 ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest); 273 return 0; 274 } 275 276 /* pop_eth does not support VLAN packets as this action is never called 277 * for them. 278 */ 279 static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key) 280 { 281 skb_pull_rcsum(skb, ETH_HLEN); 282 skb_reset_mac_header(skb); 283 skb_reset_mac_len(skb); 284 285 /* safe right before invalidate_flow_key */ 286 key->mac_proto = MAC_PROTO_NONE; 287 invalidate_flow_key(key); 288 return 0; 289 } 290 291 static int push_eth(struct sk_buff *skb, struct sw_flow_key *key, 292 const struct ovs_action_push_eth *ethh) 293 { 294 struct ethhdr *hdr; 295 296 /* Add the new Ethernet header */ 297 if (skb_cow_head(skb, ETH_HLEN) < 0) 298 return -ENOMEM; 299 300 skb_push(skb, ETH_HLEN); 301 skb_reset_mac_header(skb); 302 skb_reset_mac_len(skb); 303 304 hdr = eth_hdr(skb); 305 ether_addr_copy(hdr->h_source, ethh->addresses.eth_src); 306 ether_addr_copy(hdr->h_dest, ethh->addresses.eth_dst); 307 hdr->h_proto = skb->protocol; 308 309 skb_postpush_rcsum(skb, hdr, ETH_HLEN); 310 311 /* safe right before invalidate_flow_key */ 312 key->mac_proto = MAC_PROTO_ETHERNET; 313 invalidate_flow_key(key); 314 return 0; 315 } 316 317 static int push_nsh(struct sk_buff *skb, struct sw_flow_key *key, 318 const struct nshhdr *nh) 319 { 320 int err; 321 322 err = nsh_push(skb, nh); 323 if (err) 324 return err; 325 326 /* safe right before invalidate_flow_key */ 327 key->mac_proto = MAC_PROTO_NONE; 328 invalidate_flow_key(key); 329 return 0; 330 } 331 332 static int pop_nsh(struct sk_buff *skb, struct sw_flow_key *key) 333 { 334 int err; 335 336 err = nsh_pop(skb); 337 if (err) 338 return err; 339 340 /* safe right before invalidate_flow_key */ 341 if (skb->protocol == htons(ETH_P_TEB)) 342 key->mac_proto = MAC_PROTO_ETHERNET; 343 else 344 key->mac_proto = MAC_PROTO_NONE; 345 invalidate_flow_key(key); 346 return 0; 347 } 348 349 static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh, 350 __be32 addr, __be32 new_addr) 351 { 352 int transport_len = skb->len - skb_transport_offset(skb); 353 354 if (nh->frag_off & htons(IP_OFFSET)) 355 return; 356 357 if (nh->protocol == IPPROTO_TCP) { 358 if (likely(transport_len >= sizeof(struct tcphdr))) 359 inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb, 360 addr, new_addr, true); 361 } else if (nh->protocol == IPPROTO_UDP) { 362 if (likely(transport_len >= sizeof(struct udphdr))) { 363 struct udphdr *uh = udp_hdr(skb); 364 365 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 366 inet_proto_csum_replace4(&uh->check, skb, 367 addr, new_addr, true); 368 if (!uh->check) 369 uh->check = CSUM_MANGLED_0; 370 } 371 } 372 } 373 } 374 375 static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh, 376 __be32 *addr, __be32 new_addr) 377 { 378 update_ip_l4_checksum(skb, nh, *addr, new_addr); 379 csum_replace4(&nh->check, *addr, new_addr); 380 skb_clear_hash(skb); 381 *addr = new_addr; 382 } 383 384 static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto, 385 __be32 addr[4], const __be32 new_addr[4]) 386 { 387 int transport_len = skb->len - skb_transport_offset(skb); 388 389 if (l4_proto == NEXTHDR_TCP) { 390 if (likely(transport_len >= sizeof(struct tcphdr))) 391 inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb, 392 addr, new_addr, true); 393 } else if (l4_proto == NEXTHDR_UDP) { 394 if (likely(transport_len >= sizeof(struct udphdr))) { 395 struct udphdr *uh = udp_hdr(skb); 396 397 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 398 inet_proto_csum_replace16(&uh->check, skb, 399 addr, new_addr, true); 400 if (!uh->check) 401 uh->check = CSUM_MANGLED_0; 402 } 403 } 404 } else if (l4_proto == NEXTHDR_ICMP) { 405 if (likely(transport_len >= sizeof(struct icmp6hdr))) 406 inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum, 407 skb, addr, new_addr, true); 408 } 409 } 410 411 static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4], 412 const __be32 mask[4], __be32 masked[4]) 413 { 414 masked[0] = OVS_MASKED(old[0], addr[0], mask[0]); 415 masked[1] = OVS_MASKED(old[1], addr[1], mask[1]); 416 masked[2] = OVS_MASKED(old[2], addr[2], mask[2]); 417 masked[3] = OVS_MASKED(old[3], addr[3], mask[3]); 418 } 419 420 static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto, 421 __be32 addr[4], const __be32 new_addr[4], 422 bool recalculate_csum) 423 { 424 if (recalculate_csum) 425 update_ipv6_checksum(skb, l4_proto, addr, new_addr); 426 427 skb_clear_hash(skb); 428 memcpy(addr, new_addr, sizeof(__be32[4])); 429 } 430 431 static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl, u32 mask) 432 { 433 /* Bits 21-24 are always unmasked, so this retains their values. */ 434 OVS_SET_MASKED(nh->flow_lbl[0], (u8)(fl >> 16), (u8)(mask >> 16)); 435 OVS_SET_MASKED(nh->flow_lbl[1], (u8)(fl >> 8), (u8)(mask >> 8)); 436 OVS_SET_MASKED(nh->flow_lbl[2], (u8)fl, (u8)mask); 437 } 438 439 static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl, 440 u8 mask) 441 { 442 new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask); 443 444 csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8)); 445 nh->ttl = new_ttl; 446 } 447 448 static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key, 449 const struct ovs_key_ipv4 *key, 450 const struct ovs_key_ipv4 *mask) 451 { 452 struct iphdr *nh; 453 __be32 new_addr; 454 int err; 455 456 err = skb_ensure_writable(skb, skb_network_offset(skb) + 457 sizeof(struct iphdr)); 458 if (unlikely(err)) 459 return err; 460 461 nh = ip_hdr(skb); 462 463 /* Setting an IP addresses is typically only a side effect of 464 * matching on them in the current userspace implementation, so it 465 * makes sense to check if the value actually changed. 466 */ 467 if (mask->ipv4_src) { 468 new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src); 469 470 if (unlikely(new_addr != nh->saddr)) { 471 set_ip_addr(skb, nh, &nh->saddr, new_addr); 472 flow_key->ipv4.addr.src = new_addr; 473 } 474 } 475 if (mask->ipv4_dst) { 476 new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst); 477 478 if (unlikely(new_addr != nh->daddr)) { 479 set_ip_addr(skb, nh, &nh->daddr, new_addr); 480 flow_key->ipv4.addr.dst = new_addr; 481 } 482 } 483 if (mask->ipv4_tos) { 484 ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos); 485 flow_key->ip.tos = nh->tos; 486 } 487 if (mask->ipv4_ttl) { 488 set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl); 489 flow_key->ip.ttl = nh->ttl; 490 } 491 492 return 0; 493 } 494 495 static bool is_ipv6_mask_nonzero(const __be32 addr[4]) 496 { 497 return !!(addr[0] | addr[1] | addr[2] | addr[3]); 498 } 499 500 static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key, 501 const struct ovs_key_ipv6 *key, 502 const struct ovs_key_ipv6 *mask) 503 { 504 struct ipv6hdr *nh; 505 int err; 506 507 err = skb_ensure_writable(skb, skb_network_offset(skb) + 508 sizeof(struct ipv6hdr)); 509 if (unlikely(err)) 510 return err; 511 512 nh = ipv6_hdr(skb); 513 514 /* Setting an IP addresses is typically only a side effect of 515 * matching on them in the current userspace implementation, so it 516 * makes sense to check if the value actually changed. 517 */ 518 if (is_ipv6_mask_nonzero(mask->ipv6_src)) { 519 __be32 *saddr = (__be32 *)&nh->saddr; 520 __be32 masked[4]; 521 522 mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked); 523 524 if (unlikely(memcmp(saddr, masked, sizeof(masked)))) { 525 set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked, 526 true); 527 memcpy(&flow_key->ipv6.addr.src, masked, 528 sizeof(flow_key->ipv6.addr.src)); 529 } 530 } 531 if (is_ipv6_mask_nonzero(mask->ipv6_dst)) { 532 unsigned int offset = 0; 533 int flags = IP6_FH_F_SKIP_RH; 534 bool recalc_csum = true; 535 __be32 *daddr = (__be32 *)&nh->daddr; 536 __be32 masked[4]; 537 538 mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked); 539 540 if (unlikely(memcmp(daddr, masked, sizeof(masked)))) { 541 if (ipv6_ext_hdr(nh->nexthdr)) 542 recalc_csum = (ipv6_find_hdr(skb, &offset, 543 NEXTHDR_ROUTING, 544 NULL, &flags) 545 != NEXTHDR_ROUTING); 546 547 set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked, 548 recalc_csum); 549 memcpy(&flow_key->ipv6.addr.dst, masked, 550 sizeof(flow_key->ipv6.addr.dst)); 551 } 552 } 553 if (mask->ipv6_tclass) { 554 ipv6_change_dsfield(nh, ~mask->ipv6_tclass, key->ipv6_tclass); 555 flow_key->ip.tos = ipv6_get_dsfield(nh); 556 } 557 if (mask->ipv6_label) { 558 set_ipv6_fl(nh, ntohl(key->ipv6_label), 559 ntohl(mask->ipv6_label)); 560 flow_key->ipv6.label = 561 *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL); 562 } 563 if (mask->ipv6_hlimit) { 564 OVS_SET_MASKED(nh->hop_limit, key->ipv6_hlimit, 565 mask->ipv6_hlimit); 566 flow_key->ip.ttl = nh->hop_limit; 567 } 568 return 0; 569 } 570 571 static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key, 572 const struct nlattr *a) 573 { 574 struct nshhdr *nh; 575 size_t length; 576 int err; 577 u8 flags; 578 u8 ttl; 579 int i; 580 581 struct ovs_key_nsh key; 582 struct ovs_key_nsh mask; 583 584 err = nsh_key_from_nlattr(a, &key, &mask); 585 if (err) 586 return err; 587 588 /* Make sure the NSH base header is there */ 589 if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN)) 590 return -ENOMEM; 591 592 nh = nsh_hdr(skb); 593 length = nsh_hdr_len(nh); 594 595 /* Make sure the whole NSH header is there */ 596 err = skb_ensure_writable(skb, skb_network_offset(skb) + 597 length); 598 if (unlikely(err)) 599 return err; 600 601 nh = nsh_hdr(skb); 602 skb_postpull_rcsum(skb, nh, length); 603 flags = nsh_get_flags(nh); 604 flags = OVS_MASKED(flags, key.base.flags, mask.base.flags); 605 flow_key->nsh.base.flags = flags; 606 ttl = nsh_get_ttl(nh); 607 ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl); 608 flow_key->nsh.base.ttl = ttl; 609 nsh_set_flags_and_ttl(nh, flags, ttl); 610 nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr, 611 mask.base.path_hdr); 612 flow_key->nsh.base.path_hdr = nh->path_hdr; 613 switch (nh->mdtype) { 614 case NSH_M_TYPE1: 615 for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) { 616 nh->md1.context[i] = 617 OVS_MASKED(nh->md1.context[i], key.context[i], 618 mask.context[i]); 619 } 620 memcpy(flow_key->nsh.context, nh->md1.context, 621 sizeof(nh->md1.context)); 622 break; 623 case NSH_M_TYPE2: 624 memset(flow_key->nsh.context, 0, 625 sizeof(flow_key->nsh.context)); 626 break; 627 default: 628 return -EINVAL; 629 } 630 skb_postpush_rcsum(skb, nh, length); 631 return 0; 632 } 633 634 /* Must follow skb_ensure_writable() since that can move the skb data. */ 635 static void set_tp_port(struct sk_buff *skb, __be16 *port, 636 __be16 new_port, __sum16 *check) 637 { 638 inet_proto_csum_replace2(check, skb, *port, new_port, false); 639 *port = new_port; 640 } 641 642 static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key, 643 const struct ovs_key_udp *key, 644 const struct ovs_key_udp *mask) 645 { 646 struct udphdr *uh; 647 __be16 src, dst; 648 int err; 649 650 err = skb_ensure_writable(skb, skb_transport_offset(skb) + 651 sizeof(struct udphdr)); 652 if (unlikely(err)) 653 return err; 654 655 uh = udp_hdr(skb); 656 /* Either of the masks is non-zero, so do not bother checking them. */ 657 src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src); 658 dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst); 659 660 if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) { 661 if (likely(src != uh->source)) { 662 set_tp_port(skb, &uh->source, src, &uh->check); 663 flow_key->tp.src = src; 664 } 665 if (likely(dst != uh->dest)) { 666 set_tp_port(skb, &uh->dest, dst, &uh->check); 667 flow_key->tp.dst = dst; 668 } 669 670 if (unlikely(!uh->check)) 671 uh->check = CSUM_MANGLED_0; 672 } else { 673 uh->source = src; 674 uh->dest = dst; 675 flow_key->tp.src = src; 676 flow_key->tp.dst = dst; 677 } 678 679 skb_clear_hash(skb); 680 681 return 0; 682 } 683 684 static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key, 685 const struct ovs_key_tcp *key, 686 const struct ovs_key_tcp *mask) 687 { 688 struct tcphdr *th; 689 __be16 src, dst; 690 int err; 691 692 err = skb_ensure_writable(skb, skb_transport_offset(skb) + 693 sizeof(struct tcphdr)); 694 if (unlikely(err)) 695 return err; 696 697 th = tcp_hdr(skb); 698 src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src); 699 if (likely(src != th->source)) { 700 set_tp_port(skb, &th->source, src, &th->check); 701 flow_key->tp.src = src; 702 } 703 dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst); 704 if (likely(dst != th->dest)) { 705 set_tp_port(skb, &th->dest, dst, &th->check); 706 flow_key->tp.dst = dst; 707 } 708 skb_clear_hash(skb); 709 710 return 0; 711 } 712 713 static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key, 714 const struct ovs_key_sctp *key, 715 const struct ovs_key_sctp *mask) 716 { 717 unsigned int sctphoff = skb_transport_offset(skb); 718 struct sctphdr *sh; 719 __le32 old_correct_csum, new_csum, old_csum; 720 int err; 721 722 err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr)); 723 if (unlikely(err)) 724 return err; 725 726 sh = sctp_hdr(skb); 727 old_csum = sh->checksum; 728 old_correct_csum = sctp_compute_cksum(skb, sctphoff); 729 730 sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src); 731 sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst); 732 733 new_csum = sctp_compute_cksum(skb, sctphoff); 734 735 /* Carry any checksum errors through. */ 736 sh->checksum = old_csum ^ old_correct_csum ^ new_csum; 737 738 skb_clear_hash(skb); 739 flow_key->tp.src = sh->source; 740 flow_key->tp.dst = sh->dest; 741 742 return 0; 743 } 744 745 static int ovs_vport_output(struct net *net, struct sock *sk, struct sk_buff *skb) 746 { 747 struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage); 748 struct vport *vport = data->vport; 749 750 if (skb_cow_head(skb, data->l2_len) < 0) { 751 kfree_skb(skb); 752 return -ENOMEM; 753 } 754 755 __skb_dst_copy(skb, data->dst); 756 *OVS_CB(skb) = data->cb; 757 skb->inner_protocol = data->inner_protocol; 758 if (data->vlan_tci & VLAN_CFI_MASK) 759 __vlan_hwaccel_put_tag(skb, data->vlan_proto, data->vlan_tci & ~VLAN_CFI_MASK); 760 else 761 __vlan_hwaccel_clear_tag(skb); 762 763 /* Reconstruct the MAC header. */ 764 skb_push(skb, data->l2_len); 765 memcpy(skb->data, &data->l2_data, data->l2_len); 766 skb_postpush_rcsum(skb, skb->data, data->l2_len); 767 skb_reset_mac_header(skb); 768 769 if (eth_p_mpls(skb->protocol)) { 770 skb->inner_network_header = skb->network_header; 771 skb_set_network_header(skb, data->network_offset); 772 skb_reset_mac_len(skb); 773 } 774 775 ovs_vport_send(vport, skb, data->mac_proto); 776 return 0; 777 } 778 779 static unsigned int 780 ovs_dst_get_mtu(const struct dst_entry *dst) 781 { 782 return dst->dev->mtu; 783 } 784 785 static struct dst_ops ovs_dst_ops = { 786 .family = AF_UNSPEC, 787 .mtu = ovs_dst_get_mtu, 788 }; 789 790 /* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is 791 * ovs_vport_output(), which is called once per fragmented packet. 792 */ 793 static void prepare_frag(struct vport *vport, struct sk_buff *skb, 794 u16 orig_network_offset, u8 mac_proto) 795 { 796 unsigned int hlen = skb_network_offset(skb); 797 struct ovs_frag_data *data; 798 799 data = this_cpu_ptr(&ovs_frag_data_storage); 800 data->dst = skb->_skb_refdst; 801 data->vport = vport; 802 data->cb = *OVS_CB(skb); 803 data->inner_protocol = skb->inner_protocol; 804 data->network_offset = orig_network_offset; 805 if (skb_vlan_tag_present(skb)) 806 data->vlan_tci = skb_vlan_tag_get(skb) | VLAN_CFI_MASK; 807 else 808 data->vlan_tci = 0; 809 data->vlan_proto = skb->vlan_proto; 810 data->mac_proto = mac_proto; 811 data->l2_len = hlen; 812 memcpy(&data->l2_data, skb->data, hlen); 813 814 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 815 skb_pull(skb, hlen); 816 } 817 818 static void ovs_fragment(struct net *net, struct vport *vport, 819 struct sk_buff *skb, u16 mru, 820 struct sw_flow_key *key) 821 { 822 u16 orig_network_offset = 0; 823 824 if (eth_p_mpls(skb->protocol)) { 825 orig_network_offset = skb_network_offset(skb); 826 skb->network_header = skb->inner_network_header; 827 } 828 829 if (skb_network_offset(skb) > MAX_L2_LEN) { 830 OVS_NLERR(1, "L2 header too long to fragment"); 831 goto err; 832 } 833 834 if (key->eth.type == htons(ETH_P_IP)) { 835 struct dst_entry ovs_dst; 836 unsigned long orig_dst; 837 838 prepare_frag(vport, skb, orig_network_offset, 839 ovs_key_mac_proto(key)); 840 dst_init(&ovs_dst, &ovs_dst_ops, NULL, 1, 841 DST_OBSOLETE_NONE, DST_NOCOUNT); 842 ovs_dst.dev = vport->dev; 843 844 orig_dst = skb->_skb_refdst; 845 skb_dst_set_noref(skb, &ovs_dst); 846 IPCB(skb)->frag_max_size = mru; 847 848 ip_do_fragment(net, skb->sk, skb, ovs_vport_output); 849 refdst_drop(orig_dst); 850 } else if (key->eth.type == htons(ETH_P_IPV6)) { 851 const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops(); 852 unsigned long orig_dst; 853 struct rt6_info ovs_rt; 854 855 if (!v6ops) 856 goto err; 857 858 prepare_frag(vport, skb, orig_network_offset, 859 ovs_key_mac_proto(key)); 860 memset(&ovs_rt, 0, sizeof(ovs_rt)); 861 dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1, 862 DST_OBSOLETE_NONE, DST_NOCOUNT); 863 ovs_rt.dst.dev = vport->dev; 864 865 orig_dst = skb->_skb_refdst; 866 skb_dst_set_noref(skb, &ovs_rt.dst); 867 IP6CB(skb)->frag_max_size = mru; 868 869 v6ops->fragment(net, skb->sk, skb, ovs_vport_output); 870 refdst_drop(orig_dst); 871 } else { 872 WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.", 873 ovs_vport_name(vport), ntohs(key->eth.type), mru, 874 vport->dev->mtu); 875 goto err; 876 } 877 878 return; 879 err: 880 kfree_skb(skb); 881 } 882 883 static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port, 884 struct sw_flow_key *key) 885 { 886 struct vport *vport = ovs_vport_rcu(dp, out_port); 887 888 if (likely(vport)) { 889 u16 mru = OVS_CB(skb)->mru; 890 u32 cutlen = OVS_CB(skb)->cutlen; 891 892 if (unlikely(cutlen > 0)) { 893 if (skb->len - cutlen > ovs_mac_header_len(key)) 894 pskb_trim(skb, skb->len - cutlen); 895 else 896 pskb_trim(skb, ovs_mac_header_len(key)); 897 } 898 899 if (likely(!mru || 900 (skb->len <= mru + vport->dev->hard_header_len))) { 901 ovs_vport_send(vport, skb, ovs_key_mac_proto(key)); 902 } else if (mru <= vport->dev->mtu) { 903 struct net *net = read_pnet(&dp->net); 904 905 ovs_fragment(net, vport, skb, mru, key); 906 } else { 907 kfree_skb(skb); 908 } 909 } else { 910 kfree_skb(skb); 911 } 912 } 913 914 static int output_userspace(struct datapath *dp, struct sk_buff *skb, 915 struct sw_flow_key *key, const struct nlattr *attr, 916 const struct nlattr *actions, int actions_len, 917 uint32_t cutlen) 918 { 919 struct dp_upcall_info upcall; 920 const struct nlattr *a; 921 int rem; 922 923 memset(&upcall, 0, sizeof(upcall)); 924 upcall.cmd = OVS_PACKET_CMD_ACTION; 925 upcall.mru = OVS_CB(skb)->mru; 926 927 for (a = nla_data(attr), rem = nla_len(attr); rem > 0; 928 a = nla_next(a, &rem)) { 929 switch (nla_type(a)) { 930 case OVS_USERSPACE_ATTR_USERDATA: 931 upcall.userdata = a; 932 break; 933 934 case OVS_USERSPACE_ATTR_PID: 935 upcall.portid = nla_get_u32(a); 936 break; 937 938 case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: { 939 /* Get out tunnel info. */ 940 struct vport *vport; 941 942 vport = ovs_vport_rcu(dp, nla_get_u32(a)); 943 if (vport) { 944 int err; 945 946 err = dev_fill_metadata_dst(vport->dev, skb); 947 if (!err) 948 upcall.egress_tun_info = skb_tunnel_info(skb); 949 } 950 951 break; 952 } 953 954 case OVS_USERSPACE_ATTR_ACTIONS: { 955 /* Include actions. */ 956 upcall.actions = actions; 957 upcall.actions_len = actions_len; 958 break; 959 } 960 961 } /* End of switch. */ 962 } 963 964 return ovs_dp_upcall(dp, skb, key, &upcall, cutlen); 965 } 966 967 static int dec_ttl_exception_handler(struct datapath *dp, struct sk_buff *skb, 968 struct sw_flow_key *key, 969 const struct nlattr *attr, bool last) 970 { 971 /* The first action is always 'OVS_DEC_TTL_ATTR_ARG'. */ 972 struct nlattr *dec_ttl_arg = nla_data(attr); 973 int rem = nla_len(attr); 974 975 if (nla_len(dec_ttl_arg)) { 976 struct nlattr *actions = nla_next(dec_ttl_arg, &rem); 977 978 if (actions) 979 return clone_execute(dp, skb, key, 0, actions, rem, 980 last, false); 981 } 982 consume_skb(skb); 983 return 0; 984 } 985 986 /* When 'last' is true, sample() should always consume the 'skb'. 987 * Otherwise, sample() should keep 'skb' intact regardless what 988 * actions are executed within sample(). 989 */ 990 static int sample(struct datapath *dp, struct sk_buff *skb, 991 struct sw_flow_key *key, const struct nlattr *attr, 992 bool last) 993 { 994 struct nlattr *actions; 995 struct nlattr *sample_arg; 996 int rem = nla_len(attr); 997 const struct sample_arg *arg; 998 bool clone_flow_key; 999 1000 /* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */ 1001 sample_arg = nla_data(attr); 1002 arg = nla_data(sample_arg); 1003 actions = nla_next(sample_arg, &rem); 1004 1005 if ((arg->probability != U32_MAX) && 1006 (!arg->probability || prandom_u32() > arg->probability)) { 1007 if (last) 1008 consume_skb(skb); 1009 return 0; 1010 } 1011 1012 clone_flow_key = !arg->exec; 1013 return clone_execute(dp, skb, key, 0, actions, rem, last, 1014 clone_flow_key); 1015 } 1016 1017 /* When 'last' is true, clone() should always consume the 'skb'. 1018 * Otherwise, clone() should keep 'skb' intact regardless what 1019 * actions are executed within clone(). 1020 */ 1021 static int clone(struct datapath *dp, struct sk_buff *skb, 1022 struct sw_flow_key *key, const struct nlattr *attr, 1023 bool last) 1024 { 1025 struct nlattr *actions; 1026 struct nlattr *clone_arg; 1027 int rem = nla_len(attr); 1028 bool dont_clone_flow_key; 1029 1030 /* The first action is always 'OVS_CLONE_ATTR_ARG'. */ 1031 clone_arg = nla_data(attr); 1032 dont_clone_flow_key = nla_get_u32(clone_arg); 1033 actions = nla_next(clone_arg, &rem); 1034 1035 return clone_execute(dp, skb, key, 0, actions, rem, last, 1036 !dont_clone_flow_key); 1037 } 1038 1039 static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key, 1040 const struct nlattr *attr) 1041 { 1042 struct ovs_action_hash *hash_act = nla_data(attr); 1043 u32 hash = 0; 1044 1045 /* OVS_HASH_ALG_L4 is the only possible hash algorithm. */ 1046 hash = skb_get_hash(skb); 1047 hash = jhash_1word(hash, hash_act->hash_basis); 1048 if (!hash) 1049 hash = 0x1; 1050 1051 key->ovs_flow_hash = hash; 1052 } 1053 1054 static int execute_set_action(struct sk_buff *skb, 1055 struct sw_flow_key *flow_key, 1056 const struct nlattr *a) 1057 { 1058 /* Only tunnel set execution is supported without a mask. */ 1059 if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) { 1060 struct ovs_tunnel_info *tun = nla_data(a); 1061 1062 skb_dst_drop(skb); 1063 dst_hold((struct dst_entry *)tun->tun_dst); 1064 skb_dst_set(skb, (struct dst_entry *)tun->tun_dst); 1065 return 0; 1066 } 1067 1068 return -EINVAL; 1069 } 1070 1071 /* Mask is at the midpoint of the data. */ 1072 #define get_mask(a, type) ((const type)nla_data(a) + 1) 1073 1074 static int execute_masked_set_action(struct sk_buff *skb, 1075 struct sw_flow_key *flow_key, 1076 const struct nlattr *a) 1077 { 1078 int err = 0; 1079 1080 switch (nla_type(a)) { 1081 case OVS_KEY_ATTR_PRIORITY: 1082 OVS_SET_MASKED(skb->priority, nla_get_u32(a), 1083 *get_mask(a, u32 *)); 1084 flow_key->phy.priority = skb->priority; 1085 break; 1086 1087 case OVS_KEY_ATTR_SKB_MARK: 1088 OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *)); 1089 flow_key->phy.skb_mark = skb->mark; 1090 break; 1091 1092 case OVS_KEY_ATTR_TUNNEL_INFO: 1093 /* Masked data not supported for tunnel. */ 1094 err = -EINVAL; 1095 break; 1096 1097 case OVS_KEY_ATTR_ETHERNET: 1098 err = set_eth_addr(skb, flow_key, nla_data(a), 1099 get_mask(a, struct ovs_key_ethernet *)); 1100 break; 1101 1102 case OVS_KEY_ATTR_NSH: 1103 err = set_nsh(skb, flow_key, a); 1104 break; 1105 1106 case OVS_KEY_ATTR_IPV4: 1107 err = set_ipv4(skb, flow_key, nla_data(a), 1108 get_mask(a, struct ovs_key_ipv4 *)); 1109 break; 1110 1111 case OVS_KEY_ATTR_IPV6: 1112 err = set_ipv6(skb, flow_key, nla_data(a), 1113 get_mask(a, struct ovs_key_ipv6 *)); 1114 break; 1115 1116 case OVS_KEY_ATTR_TCP: 1117 err = set_tcp(skb, flow_key, nla_data(a), 1118 get_mask(a, struct ovs_key_tcp *)); 1119 break; 1120 1121 case OVS_KEY_ATTR_UDP: 1122 err = set_udp(skb, flow_key, nla_data(a), 1123 get_mask(a, struct ovs_key_udp *)); 1124 break; 1125 1126 case OVS_KEY_ATTR_SCTP: 1127 err = set_sctp(skb, flow_key, nla_data(a), 1128 get_mask(a, struct ovs_key_sctp *)); 1129 break; 1130 1131 case OVS_KEY_ATTR_MPLS: 1132 err = set_mpls(skb, flow_key, nla_data(a), get_mask(a, 1133 __be32 *)); 1134 break; 1135 1136 case OVS_KEY_ATTR_CT_STATE: 1137 case OVS_KEY_ATTR_CT_ZONE: 1138 case OVS_KEY_ATTR_CT_MARK: 1139 case OVS_KEY_ATTR_CT_LABELS: 1140 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4: 1141 case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6: 1142 err = -EINVAL; 1143 break; 1144 } 1145 1146 return err; 1147 } 1148 1149 static int execute_recirc(struct datapath *dp, struct sk_buff *skb, 1150 struct sw_flow_key *key, 1151 const struct nlattr *a, bool last) 1152 { 1153 u32 recirc_id; 1154 1155 if (!is_flow_key_valid(key)) { 1156 int err; 1157 1158 err = ovs_flow_key_update(skb, key); 1159 if (err) 1160 return err; 1161 } 1162 BUG_ON(!is_flow_key_valid(key)); 1163 1164 recirc_id = nla_get_u32(a); 1165 return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true); 1166 } 1167 1168 static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb, 1169 struct sw_flow_key *key, 1170 const struct nlattr *attr, bool last) 1171 { 1172 const struct nlattr *actions, *cpl_arg; 1173 const struct check_pkt_len_arg *arg; 1174 int rem = nla_len(attr); 1175 bool clone_flow_key; 1176 1177 /* The first netlink attribute in 'attr' is always 1178 * 'OVS_CHECK_PKT_LEN_ATTR_ARG'. 1179 */ 1180 cpl_arg = nla_data(attr); 1181 arg = nla_data(cpl_arg); 1182 1183 if (skb->len <= arg->pkt_len) { 1184 /* Second netlink attribute in 'attr' is always 1185 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL'. 1186 */ 1187 actions = nla_next(cpl_arg, &rem); 1188 clone_flow_key = !arg->exec_for_lesser_equal; 1189 } else { 1190 /* Third netlink attribute in 'attr' is always 1191 * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER'. 1192 */ 1193 actions = nla_next(cpl_arg, &rem); 1194 actions = nla_next(actions, &rem); 1195 clone_flow_key = !arg->exec_for_greater; 1196 } 1197 1198 return clone_execute(dp, skb, key, 0, nla_data(actions), 1199 nla_len(actions), last, clone_flow_key); 1200 } 1201 1202 static int execute_dec_ttl(struct sk_buff *skb, struct sw_flow_key *key) 1203 { 1204 int err; 1205 1206 if (skb->protocol == htons(ETH_P_IPV6)) { 1207 struct ipv6hdr *nh; 1208 1209 err = skb_ensure_writable(skb, skb_network_offset(skb) + 1210 sizeof(*nh)); 1211 if (unlikely(err)) 1212 return err; 1213 1214 nh = ipv6_hdr(skb); 1215 1216 if (nh->hop_limit <= 1) 1217 return -EHOSTUNREACH; 1218 1219 key->ip.ttl = --nh->hop_limit; 1220 } else { 1221 struct iphdr *nh; 1222 u8 old_ttl; 1223 1224 err = skb_ensure_writable(skb, skb_network_offset(skb) + 1225 sizeof(*nh)); 1226 if (unlikely(err)) 1227 return err; 1228 1229 nh = ip_hdr(skb); 1230 if (nh->ttl <= 1) 1231 return -EHOSTUNREACH; 1232 1233 old_ttl = nh->ttl--; 1234 csum_replace2(&nh->check, htons(old_ttl << 8), 1235 htons(nh->ttl << 8)); 1236 key->ip.ttl = nh->ttl; 1237 } 1238 return 0; 1239 } 1240 1241 /* Execute a list of actions against 'skb'. */ 1242 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, 1243 struct sw_flow_key *key, 1244 const struct nlattr *attr, int len) 1245 { 1246 const struct nlattr *a; 1247 int rem; 1248 1249 for (a = attr, rem = len; rem > 0; 1250 a = nla_next(a, &rem)) { 1251 int err = 0; 1252 1253 switch (nla_type(a)) { 1254 case OVS_ACTION_ATTR_OUTPUT: { 1255 int port = nla_get_u32(a); 1256 struct sk_buff *clone; 1257 1258 /* Every output action needs a separate clone 1259 * of 'skb', In case the output action is the 1260 * last action, cloning can be avoided. 1261 */ 1262 if (nla_is_last(a, rem)) { 1263 do_output(dp, skb, port, key); 1264 /* 'skb' has been used for output. 1265 */ 1266 return 0; 1267 } 1268 1269 clone = skb_clone(skb, GFP_ATOMIC); 1270 if (clone) 1271 do_output(dp, clone, port, key); 1272 OVS_CB(skb)->cutlen = 0; 1273 break; 1274 } 1275 1276 case OVS_ACTION_ATTR_TRUNC: { 1277 struct ovs_action_trunc *trunc = nla_data(a); 1278 1279 if (skb->len > trunc->max_len) 1280 OVS_CB(skb)->cutlen = skb->len - trunc->max_len; 1281 break; 1282 } 1283 1284 case OVS_ACTION_ATTR_USERSPACE: 1285 output_userspace(dp, skb, key, a, attr, 1286 len, OVS_CB(skb)->cutlen); 1287 OVS_CB(skb)->cutlen = 0; 1288 break; 1289 1290 case OVS_ACTION_ATTR_HASH: 1291 execute_hash(skb, key, a); 1292 break; 1293 1294 case OVS_ACTION_ATTR_PUSH_MPLS: { 1295 struct ovs_action_push_mpls *mpls = nla_data(a); 1296 1297 err = push_mpls(skb, key, mpls->mpls_lse, 1298 mpls->mpls_ethertype, skb->mac_len); 1299 break; 1300 } 1301 case OVS_ACTION_ATTR_ADD_MPLS: { 1302 struct ovs_action_add_mpls *mpls = nla_data(a); 1303 __u16 mac_len = 0; 1304 1305 if (mpls->tun_flags & OVS_MPLS_L3_TUNNEL_FLAG_MASK) 1306 mac_len = skb->mac_len; 1307 1308 err = push_mpls(skb, key, mpls->mpls_lse, 1309 mpls->mpls_ethertype, mac_len); 1310 break; 1311 } 1312 case OVS_ACTION_ATTR_POP_MPLS: 1313 err = pop_mpls(skb, key, nla_get_be16(a)); 1314 break; 1315 1316 case OVS_ACTION_ATTR_PUSH_VLAN: 1317 err = push_vlan(skb, key, nla_data(a)); 1318 break; 1319 1320 case OVS_ACTION_ATTR_POP_VLAN: 1321 err = pop_vlan(skb, key); 1322 break; 1323 1324 case OVS_ACTION_ATTR_RECIRC: { 1325 bool last = nla_is_last(a, rem); 1326 1327 err = execute_recirc(dp, skb, key, a, last); 1328 if (last) { 1329 /* If this is the last action, the skb has 1330 * been consumed or freed. 1331 * Return immediately. 1332 */ 1333 return err; 1334 } 1335 break; 1336 } 1337 1338 case OVS_ACTION_ATTR_SET: 1339 err = execute_set_action(skb, key, nla_data(a)); 1340 break; 1341 1342 case OVS_ACTION_ATTR_SET_MASKED: 1343 case OVS_ACTION_ATTR_SET_TO_MASKED: 1344 err = execute_masked_set_action(skb, key, nla_data(a)); 1345 break; 1346 1347 case OVS_ACTION_ATTR_SAMPLE: { 1348 bool last = nla_is_last(a, rem); 1349 1350 err = sample(dp, skb, key, a, last); 1351 if (last) 1352 return err; 1353 1354 break; 1355 } 1356 1357 case OVS_ACTION_ATTR_CT: 1358 if (!is_flow_key_valid(key)) { 1359 err = ovs_flow_key_update(skb, key); 1360 if (err) 1361 return err; 1362 } 1363 1364 err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key, 1365 nla_data(a)); 1366 1367 /* Hide stolen IP fragments from user space. */ 1368 if (err) 1369 return err == -EINPROGRESS ? 0 : err; 1370 break; 1371 1372 case OVS_ACTION_ATTR_CT_CLEAR: 1373 err = ovs_ct_clear(skb, key); 1374 break; 1375 1376 case OVS_ACTION_ATTR_PUSH_ETH: 1377 err = push_eth(skb, key, nla_data(a)); 1378 break; 1379 1380 case OVS_ACTION_ATTR_POP_ETH: 1381 err = pop_eth(skb, key); 1382 break; 1383 1384 case OVS_ACTION_ATTR_PUSH_NSH: { 1385 u8 buffer[NSH_HDR_MAX_LEN]; 1386 struct nshhdr *nh = (struct nshhdr *)buffer; 1387 1388 err = nsh_hdr_from_nlattr(nla_data(a), nh, 1389 NSH_HDR_MAX_LEN); 1390 if (unlikely(err)) 1391 break; 1392 err = push_nsh(skb, key, nh); 1393 break; 1394 } 1395 1396 case OVS_ACTION_ATTR_POP_NSH: 1397 err = pop_nsh(skb, key); 1398 break; 1399 1400 case OVS_ACTION_ATTR_METER: 1401 if (ovs_meter_execute(dp, skb, key, nla_get_u32(a))) { 1402 consume_skb(skb); 1403 return 0; 1404 } 1405 break; 1406 1407 case OVS_ACTION_ATTR_CLONE: { 1408 bool last = nla_is_last(a, rem); 1409 1410 err = clone(dp, skb, key, a, last); 1411 if (last) 1412 return err; 1413 1414 break; 1415 } 1416 1417 case OVS_ACTION_ATTR_CHECK_PKT_LEN: { 1418 bool last = nla_is_last(a, rem); 1419 1420 err = execute_check_pkt_len(dp, skb, key, a, last); 1421 if (last) 1422 return err; 1423 1424 break; 1425 } 1426 1427 case OVS_ACTION_ATTR_DEC_TTL: 1428 err = execute_dec_ttl(skb, key); 1429 if (err == -EHOSTUNREACH) { 1430 err = dec_ttl_exception_handler(dp, skb, key, 1431 a, true); 1432 return err; 1433 } 1434 break; 1435 } 1436 1437 if (unlikely(err)) { 1438 kfree_skb(skb); 1439 return err; 1440 } 1441 } 1442 1443 consume_skb(skb); 1444 return 0; 1445 } 1446 1447 /* Execute the actions on the clone of the packet. The effect of the 1448 * execution does not affect the original 'skb' nor the original 'key'. 1449 * 1450 * The execution may be deferred in case the actions can not be executed 1451 * immediately. 1452 */ 1453 static int clone_execute(struct datapath *dp, struct sk_buff *skb, 1454 struct sw_flow_key *key, u32 recirc_id, 1455 const struct nlattr *actions, int len, 1456 bool last, bool clone_flow_key) 1457 { 1458 struct deferred_action *da; 1459 struct sw_flow_key *clone; 1460 1461 skb = last ? skb : skb_clone(skb, GFP_ATOMIC); 1462 if (!skb) { 1463 /* Out of memory, skip this action. 1464 */ 1465 return 0; 1466 } 1467 1468 /* When clone_flow_key is false, the 'key' will not be change 1469 * by the actions, then the 'key' can be used directly. 1470 * Otherwise, try to clone key from the next recursion level of 1471 * 'flow_keys'. If clone is successful, execute the actions 1472 * without deferring. 1473 */ 1474 clone = clone_flow_key ? clone_key(key) : key; 1475 if (clone) { 1476 int err = 0; 1477 1478 if (actions) { /* Sample action */ 1479 if (clone_flow_key) 1480 __this_cpu_inc(exec_actions_level); 1481 1482 err = do_execute_actions(dp, skb, clone, 1483 actions, len); 1484 1485 if (clone_flow_key) 1486 __this_cpu_dec(exec_actions_level); 1487 } else { /* Recirc action */ 1488 clone->recirc_id = recirc_id; 1489 ovs_dp_process_packet(skb, clone); 1490 } 1491 return err; 1492 } 1493 1494 /* Out of 'flow_keys' space. Defer actions */ 1495 da = add_deferred_actions(skb, key, actions, len); 1496 if (da) { 1497 if (!actions) { /* Recirc action */ 1498 key = &da->pkt_key; 1499 key->recirc_id = recirc_id; 1500 } 1501 } else { 1502 /* Out of per CPU action FIFO space. Drop the 'skb' and 1503 * log an error. 1504 */ 1505 kfree_skb(skb); 1506 1507 if (net_ratelimit()) { 1508 if (actions) { /* Sample action */ 1509 pr_warn("%s: deferred action limit reached, drop sample action\n", 1510 ovs_dp_name(dp)); 1511 } else { /* Recirc action */ 1512 pr_warn("%s: deferred action limit reached, drop recirc action\n", 1513 ovs_dp_name(dp)); 1514 } 1515 } 1516 } 1517 return 0; 1518 } 1519 1520 static void process_deferred_actions(struct datapath *dp) 1521 { 1522 struct action_fifo *fifo = this_cpu_ptr(action_fifos); 1523 1524 /* Do not touch the FIFO in case there is no deferred actions. */ 1525 if (action_fifo_is_empty(fifo)) 1526 return; 1527 1528 /* Finishing executing all deferred actions. */ 1529 do { 1530 struct deferred_action *da = action_fifo_get(fifo); 1531 struct sk_buff *skb = da->skb; 1532 struct sw_flow_key *key = &da->pkt_key; 1533 const struct nlattr *actions = da->actions; 1534 int actions_len = da->actions_len; 1535 1536 if (actions) 1537 do_execute_actions(dp, skb, key, actions, actions_len); 1538 else 1539 ovs_dp_process_packet(skb, key); 1540 } while (!action_fifo_is_empty(fifo)); 1541 1542 /* Reset FIFO for the next packet. */ 1543 action_fifo_init(fifo); 1544 } 1545 1546 /* Execute a list of actions against 'skb'. */ 1547 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb, 1548 const struct sw_flow_actions *acts, 1549 struct sw_flow_key *key) 1550 { 1551 int err, level; 1552 1553 level = __this_cpu_inc_return(exec_actions_level); 1554 if (unlikely(level > OVS_RECURSION_LIMIT)) { 1555 net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n", 1556 ovs_dp_name(dp)); 1557 kfree_skb(skb); 1558 err = -ENETDOWN; 1559 goto out; 1560 } 1561 1562 OVS_CB(skb)->acts_origlen = acts->orig_len; 1563 err = do_execute_actions(dp, skb, key, 1564 acts->actions, acts->actions_len); 1565 1566 if (level == 1) 1567 process_deferred_actions(dp); 1568 1569 out: 1570 __this_cpu_dec(exec_actions_level); 1571 return err; 1572 } 1573 1574 int action_fifos_init(void) 1575 { 1576 action_fifos = alloc_percpu(struct action_fifo); 1577 if (!action_fifos) 1578 return -ENOMEM; 1579 1580 flow_keys = alloc_percpu(struct action_flow_keys); 1581 if (!flow_keys) { 1582 free_percpu(action_fifos); 1583 return -ENOMEM; 1584 } 1585 1586 return 0; 1587 } 1588 1589 void action_fifos_exit(void) 1590 { 1591 free_percpu(action_fifos); 1592 free_percpu(flow_keys); 1593 } 1594